added convenience macro
added convenience macro

nmacs/tinydtls,jvermillard/tinydtls,nmacs/tinydtls,spark/tinydtls,malvira/tinydtls-code,jvermillard/tinydtls,thecodemaiden/tinydtls-fork,nmacs/tinydtls,yunus/TinyDTLS-WebID,yunus/TinyDTLS-WebID,fvdnabee/tinydtls,malvira/tinydtls-code,OlegHahm/tinydtls,LaKabane/tinydtls,thecodemaiden/tinydtls-fork,thecodemaiden/tinydtls-fork,spark/tinydtls,jvermillard/tinydtls,fvdnabee/tinydtls,nmacs/tinydtls,OlegHahm/tinydtls,spark/tinydtls,LaKabane/tinydtls,OlegHahm/tinydtls,yunus/TinyDTLS-WebID,fvdnabee/tinydtls